It is basically known to utilize containers for storing and/or for transporting objects, e.g., hardware such as screws, nuts or electronic components, i.e., generally piece goods or also bulk materials.
Containers of this type may be used as transport containers and/or storage containers, for example, in a storage facility with high-bay racks. In this case, the containers may also be used in a combined fashion, e.g., by storing containers in a high-bay rack facility in the form of storage containers and transporting said containers to another location such as, if applicable, a mobile work station in the form of transport containers such that they serve as a decentralized storage site for certain piece goods or bulk materials for a certain period of time.
Conventional transport and/or storage containers that form part of a warehousing or inventory management system usually involve a high effort if it is important to ensure that a sufficient supply of piece goods or the bulk material is always available. For this purpose, it is necessary to log the filling and the withdrawal processes for the individual containers. In order to correct errors that can inevitably occur over time, it is required to regularly take stock of all stored articles in the form of a manual count. The effort involved with such stock-taking processes, as well as the effort for detecting the input and the withdrawal of goods into/from the containers in the form of a logistics system, is personnel-intensive and cost-intensive, but still error-prone.
For example, EP 0 952 432 A1 discloses a system for detecting a material quantity in a container. For this purpose, infrared light sources and infrared light sensors are arranged behind container side walls that lie opposite of one another and are transparent to infrared light such that infrared light emitted into the container by the infrared light sources is absorbed or reflected by the material contained therein and can be received with oppositely arranged infrared light sensors in such a way that the fill level of the container can be determined. With respect to a certain material quantity, however, this method is only sufficiently accurate at high fill levels because the relative measuring error increases as the fill level decreases. This is particularly problematic with articles in the form of the initially mentioned piece goods or bulk materials because the detection of a certain residual quantity usually serves as a trigger (notification limit) for reordering the article in a timely fashion. It is therefore important to detect the current residual quantity as accurately as possible when the number of articles situated in the container approaches the notification limit.
One potential objective can be seen in proposing a correspondingly improved method for detecting the fill level in a container for transporting and/or storing objects, particularly piece goods or bulk materials, with a container bottom and an inner container wall, making available a container suitable for carrying out the method and proposing a system for dynamically monitoring the fill level of a plurality of such containers.